Somehow she had obtained possession of the evidence — the chief evidence — against Knowlton, and destroyed it! And he had calmly looked on, like a weak fool! Why had he not had sense enough to stop her when she had first left the house? These were the thoughts that whipped him into a frenzy of rage.

But Sherman was not the man to waste time crying over spilled milk. After all, he reflected, the damage was not irreparable, since his knowledge gave him a power over her that should prove irresistible. By the time the boat had returned to Twenty-third Street he was once more fiercely exultant.

But he took the precaution of following Lila uptown; nor was he satisfied until he saw her white face dimly outlined at her own window.

Then he turned, muttering: “I guess she’ll do no more mischief tonight.”

He was determined that he would not make a second mistake. The first thing was to make sure of Knowlton. Perhaps early in the morning — He glanced at his watch; it was a quarter past nine.

At the corner he turned into a saloon and telephoned the office of Detective Barrett, and, finding him in, made an appointment to call on him in three-quarters of an hour.

He was there five minutes ahead of time. The detective was alone in the office and opened the door himself in response to his visitor’s knock.

He was in ill humor.

“You’ve got us in a pretty mess,” he began, placing a chair for Sherman and seating himself at his desk. “We got Knowlton all right, but there wasn’t a scrap of stuff in the whole place. Unless we can dig up something, what he can do to us won’t be a little. That was a beautiful tip-off of yours — I don’t think. I don’t say it wasn’t on the square, but it looks like—”

Sherman cut him short.

“Wait a minute, Barrett. You shut your eyes and go to sleep, and then when you don’t see anything you blame it on me. The stuff was there, and it’s your own fault you didn’t get it.”

“Then you’d better go up there and show it to Corliss. He’s probably looking for it yet.”

“Oh, he won’t find it now.” Sherman leaned forward in his chair and held up a finger impressively. “When you went in that house Knowlton wasn’t alone. There was a woman in his rooms with him, and a big bundle of the queer. And you politely closed your eyes and let her walk out with it.”

The other stared at him.

“What sort of a game is this?” he demanded.

“This is straight,” said Sherman, “and I can prove it. I know who the woman was, and I know what she did with the stuff. What I can’t understand is how she ever got away.”

“Do you mean to say she was inside when we got there?”

Sherman nodded emphatically.

The detective looked puzzled:

“Then how in the name of—” He stopped short, while his face was suddenly filled with the light of understanding — and chagrin.

“Well, I’m jiggered,” he said finally. Then he explained Knowlton’s ruse — or rather Lila’s — to Sherman. “It’s an old trick,” he ended, “but we weren’t looking for it. We thought he was alone. But where did she go? What did she do with it? Who is she?”

“She took a ride on a ferryboat and dropped it in the middle of the Hudson.”

“Then it’s gone.”

“Thanks to you, yes.”

“But where did you get all this? Of course, she’s a—”

“Back up!” Sherman interrupted. “She’s a friend of mine.”

“She seems not exactly to hate Knowlton,” the detective observed dryly. “Who is she?”

Sherman winced.

“What does that matter? She knows enough to send him higher than a kite, and she’ll have to come through with it.”

The other became impatient.

“But who is she? We ought to get her tonight.”

There was a pause; then Sherman said slowly:

“You won’t get her at all.”

At the look of inquiry and surprise on the detective’s face he proceeded to explain:

“I told you she’s a friend of mine. Maybe it would be better to say I’m a friend of hers. Put it however you please, but she’s not to be locked up. Serve her as a witness, and she’ll give you all you need against Knowlton, and more, too.

“I’ll see to that. She can’t get out of it. Anyway, if you arrested her, what would happen? You couldn’t make them testify against each other, and they’d both get off.”

“But as soon as we serve her she’ll beat it,” the other objected.

“Leave that to me. Of course, I’ve got a personal interest in this, and you ought to consider it. I don’t have to remind you—”

“No,” the detective interrupted hastily, “you don’t. I have a memory, Billy.”

“Well, then it’s up to you.”

The detective finally capitulated and agreed to do as Sherman wished. Sherman gave him Lila’s name and address, and advised him to postpone serving the subpoena as long as possible.

“I want to prepare her for it,” he explained as the detective accompanied him to the door. “I’ll see her first thing in the morning. If possible, we want to prevent Knowlton from knowing that she is to appear against him, and I think I can manage it. You’ll hear from me tomorrow. Going uptown?”

The other replied that he had work to do in the office that would keep him till midnight, and wished him good night.

Sherman was well satisfied with the day’s work. With Knowlton in the Tombs and Lila completely in his power, he felt that there was nothing left to be desired. As he sat in an uptown subway local he reviewed his position with the eye of a general, and, discovering no possible loophole for the enemy, sighed with satisfaction.

At Twenty-third Street he left the train and made his way to the lobby of the Lamartine.

He was led there more by force of habit than by any particular purpose. At first he had thought of going to see Lila at once, but had decided that it would serve his ends better to allow her to have a night for reflection over the day’s events. She would be less able to resist his demands.

It was but little past ten o’clock, and he found the lobby almost deserted. Night at the Lamartine began late and ended early — in the morning.

One or two nondescripts loitered about the entrance inside, the hotel clerk yawned behind his desk, and the weary-looking female who took Miss Hughes’s place during the hours of darkness was drumming on the counter with her fingers, chewing gum, and reading a newspaper, thus exercising three different sets of muscles at the same time.

Sherman approached her:

“Have any of the boys been in?”

She looked up from her newspaper and regarded him chillingly:

“Huh?”

It was this young girl’s habit never to understand questions addressed to her till they had been repeated at least once. It argued a superiority over the questioner; an indifference to common and sublunary affairs.

She condescended finally to inform Sherman that Driscoll and Booth had been seen in the lobby some two hours before. While talking she contrived somehow to lose not a single stroke on the gum.

Sherman wandered about for half an hour, tried to find someone to take a cue at billiards without success, and had about decided to go home when Dumain and Dougherty entered arm-in-arm.

Dumain called to Sherman, and the three proceeded to the bar. Sherman ordered a whisky, Dougherty a gin rickey, and Dumain an absinth frappé. This is for the benefit of those who judge a man by what he drinks. You see what it amounts to.

The ex-prizefighter was a little ill at ease. He felt that he had treated Sherman a little shabbily by breaking his promise not to speak to Knowlton till the following day; perhaps, after all, he thought, Sherman had acted in good faith.

“I suppose you called off your sleuth,” he observed.

Sherman looked up quickly.

“What? Oh, yes. I saw him this afternoon. Good thing, too. He was costing me more than a prima donna. Fill ’em up, bartender.”

“Then it’s all right to speak to Knowlton now?”

“As far as I’m concerned, yes.”

“The reason I wanted to know,” Dougherty hesitated, “is because I already spoke to him. It wasn’t because I wanted to put anything over on you — don’t think that. He came in here about noon, and it was too good a chance to pass up.

“Besides, Miss Williams was going out with him, and I had to head him off somehow. I was a little uneasy about it, but since you say it’s all right, I’ll forget it. And, thank Heaven, we’ve seen the last of Knowlton. By this time he’s probably so far away from little old New York you couldn’t see him with a telescope from the top of the Singer Building.”

“Well, you didn’t do any harm.” Sherman was picking up his change on the bar.

“Eet was best,” put in Dumain. “Zee sooner zee bettaire. He was a quiet scoundrel. You should have seen heem when Dougherty told heem! He had not a word. He walked out wiz a frown.”

Each man lifted his glass in silence. Each had his own thoughts.

“I’m a little worried about Miss Williams,” said Dougherty presently. “I wonder what she thought when she saw him walk out without speaking to her? Knowlton asked me to tell her, but I didn’t have the nerve. I think they had a date to go to lunch. And all afternoon she kept watching for him. I saw her.”

“She’ll soon forget him,” said Sherman.

“I doubt it,” declared Dougherty. “You know yourself he was different from us. And from the way she looked this afternoon — I doubt it.”

“Bah!” Dumain snapped his fingers. “She care not zat much for heem. If she did would she not have been — ah, grief — distrait — when she hear he was a what you call eet counterfeiter?”

There was a sudden pause, while Dougherty turned and gazed at Dumain keenly.